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The abundance of the eel (Anguilla anguilla) in Europe has been on the decline in recent years, to the extent that this fish species is now considered to be threatened with extinction. Hence, the current implementation of the Eel Management Plan in Poland, whose aim is to restore w stocks of this fish. The main natural habitats of eel are the transitional waters of the Vistula and Szczecin lagoons and lakes in northern Poland. The eel is highly valued by many consumers for the taste and texture of its meat. The aim of the study was to determine differences in concentrations of macro- and microelements and toxic metals in muscles of the eel as a function of each specimen’s length, mass and the origin. The results of the study also served an evaluation of the health benefits and risks to consumers of eel meat with regard to the content of macro- and microelements and toxic metals. Specimens of the eel (Anguilla anguilla) were caught in 2011-2013, in five regions of Poland: the southern Baltic, inland lakes in northeast Poland, the Vistula and Szczecin lagoons, and in the Vistula River. The concentrations of Ca, P, Mg, Na, K, Fe, Sr, Zn and As were determined with optical emission spectrometry. The flameless atomic absorption spectrometry method was used to measure concentrations of Cu, Cd and Pb. The content of Hg and Se were determined with atomic absorption, those of mercury with cold vapour, and of selenium with hydride generation. The concentrations of macro- and microelements in most instances, with the exception of P and Zn, were negatively correlated with the eel’s length and mass, which indicated that small fish contained more minerals than large specimens. The eel is a rich source of phosphorus, zinc, selenium and iron, and it can supply significant quantities of the daily requirements of human consumers for these minerals. The other minerals occurred in eel muscle at levels that ranged from 2 to 6% of human daily requirements. Among the toxic metals, mercury was the cause for concern, while cadmium and lead occurred at low levels in all of the specimens examined regardless of their size. The mean concentration of mercury ranged from 0.147 to 0.273 mg kg-1 and was positively correlated with specimen length and mass. The content of mercury in large eel exceeded 0.500 mg kg-1, while small eel (up to 70 cm) contained lower levels of mercury. Large eel exceeding 70 cm can pose a threat to the consumer’s health because of mercury, and especially its organic from of methylmercury. This is why consumers should limit long-term consumption of larger eel, while it is safe to consume smaller specimens since they contain less mercury and more minerals than do large eel.
The paper presents an analysis of the impact of meteorological factors (solar radiation, maximum, minimum and mean temperature, precipitation) on the development and yield of yellow lupin Parys cultivar in the northern Poland in the years 1987–2008. Using multiple regression methods (linear and quadratic function) created regression equations that were estimated using the coeffi cients of determination (R2, R2 adj and R2 pred – using the Cross Validation procedure). Selected regression equation used to estimate the yield of yellow lupin, using generated – by means of model WGENK – daily values of global radiation, maximum and minimum temperature, precipitation, and climate change scenario GISS Model E for Central Europe. Examined dependencies weather-yield of lupine seeds (cultivar Parys) allowed the application of the chosen model to forecast yields from the time when the values are independent variables in the model by the end of the growing season. The comparison of distributions of actual and simulated yields shows that real yields are slightly (by 0.06 t·ha–1) higher than those generated for 2 × CO2 conditions.
Samples of hair collected in 2004-2007 from 416 persons living in Central Pomerania were analyzed. The subjects donating hair represented a vast spectrum of age, from a tenmonth- old child to a 75-year-old person. The subjects were selected randomly. Lead and cadmium were determined by atomic absorption spectrophotometry using an ASA-3 spectrometer. The average content of the metals in the hair samples was 3.20 μg g–1 (Pb) and 0.284 μg g–1 (Cd). The highest concentration of lead in human hair (about 3.88 μg g–1) was determined for the age group 61-75 years, and that of cadmium (0.406 μg g–1) – for the age group 26-50 years. The lowest concentrations of these metals in human hair (2.07 and 0.152 μg g–1, respectively) were determined for the age group of 0-15 years. Most hair samples (50%) contained 2.01-4.00 μg g–1 Pb, while 45% of the samples contained 0.001- -0.300 μg g–1 of cadmium. Studying the dependence of the content of lead and cadmium in hair on the gender of subjects, it was discovered that in all age groups males had more lead and cadmium (3.79 and 0.334 μg g–1, respectively) than females (2.63 μg g–1 and 0.236 μg g–1). This study has also demonstrated that the environment affects the content of the analyzed metals in hair. The average value of lead and cadmium concentrations for people living in the country were 2.39 μg g–1 for Pb and 0.214 μg g–1 for Cd, while for the people living in towns and cities, the respective values were 4.17 and 0.361 μg g–1. The present study has demonstrated how nutrition affects lead and cadmium content in human hair. Among the subjects, 17% had been on some kind of a diet, predominatly easily digestible and light foods. The lowest content of these metals (on average, 2.08 μg g–1 Pb and 0.141 μg g–1 Cd) was found in hair of people on a diet, while the hiest levels (3.54 μg g–1 Pb and 0.315 μg g–1 Cd) were determined in people who did not limit consumption of meat and dairy products. Among the analyzed population, 241 persons suffered from chronic disease. The average content of lead and cadmium in hair of healthy subjects was 3.05 μg g–1 Pb and 0.257 μg g–1 Cd, but in patients suffering from arthrosclerosis, allergy and hyperplasia prostate the levels of lead and cadmium in hair reached the upper values of the se limits. Hair of the patients who suffered from cardiovascular disease showed deificiency of these metals (on average, 1.73 μg g–1 Pb and 0.182 μg g–1 Cd).
Life history traits of birds like survival or reproduction are strongly related to habitat features which affect food and nest-site availability. However, impact of habitat variables on life-history traits, which may be scale-dependent is barely studied. We investigated the relationships between landscape features and productivity (expressed as the number of 21–38 day old chicks per nest) of a colonial waterbird, the Grey Heron Ardea cinerea in northern Poland. In 2014 we analysed the landscape features (hydrographic features, habitat area, habitat patchiness and distances to the nearest water bodies, coastline, rivers/canals, buildings and roads) around the six colonies. We analysed all those features in four spatial scales around the colony: close proximity of the colony (0–1 km), closer foraging grounds (0–10 km), far foraging grounds (0–20 km) and far foraging grounds excluding close foraging areas and proximity of the colony (10–20 km). The differences in productivity among the colonies was not significant in the studied year (mean number of chicks ± SD: 3.57 ± 0.52). At each spatial scale excluding 10–20 km radius, Grey Heron productivity increased with increasing habitat heterogeneity and decreased with increasing length of rivers/canals and area of pastures. The results of this study indicate that the spatial scale of 0–10 km was the best to indicate relationships between landscape features and productivity in herons. Distance to the nearest river/canal banks, buildings and roads were related positively to productivity. Our study revealed the importance of landscape complexity of aquatic and terrestrial habitats for the Grey Heron productivity.
The studies on boron concentrations were carried out on the samples collected from the groundwater intakes located in Northern Poland in the Lower Vistula Valley and in the Starogard Lakeland with diversified hydro-geological conditions and depths. The 57 samples of water for assays were collected from the following intakes: Tczew “Park” and Tczew “Motława”, Gniew, Wielkie Walichnowy, Małe Walichnowy, and Pelplin. The deepest drillings extended to 180 m (cretaceous stages), out of which 20% comprised quaternary formations up to 123 m deep. The analysis of water samples in these regions was performed from 2009-2011. The geological architecture of these areas was identified based on the legal documentation on water utilization submitted by the operators of the water intakes. The Polish sanitary regulations specify that the maximum content of boron in drinking water is 1.0 mg dm-3. That it was found in the waters mesoregion Starogard Lakeland may be assumed to be good in the context of chemical status, because in all of the 24 water samples tested, the boron concentration did not exceed the threshold value. In the Lower Vistula Valley mesoregion in 17 samples out of 33 tested, the level of boron exceeded 1.0 mg dm-3, which means that prior to consumption these waters require treatment to reduce the concentration of this element to the permissible limits. Slightly higher concentrations of boron (on average 1.63 mg dm-3) were detected in water deposited in the cretaceous formations situated in Wielkie Wachlinowy and Małe Wachlinowy. It was also found that the content of boron in groundwater depended on the nature of geological layers from which the tested water samples were collected. The statistical analysis demonstrates that the aquifer stages exerted a significant impact on the content of boron in the tested water samples and the differences between them are significant.
Large areas of the Łeba River catchment are inaccessible for fish because of barriers, and this reduces significantly their spawning possibilities. The sea trout Salmo trutta L. population in the Łeba River is sustained through compensatory stocking with smolts. In the autumn of 2007 and 2008, seventy two sea trout were caught in a lake, through which the river flows, several kilometers upstream from its mouth. These individuals were tagged with radio transmitters that were recorded by two automatic stations in the river. They were also monitored with active telemetry. Only 26 of these fish moved upstream (41% in 2007 and 33% in 2008), and five reached the spawning grounds. Neither the release location in the lake nor the size of the fish influenced the timing of the fish entering the river or the extent of their migration. Among the fish originated from smolt stocked in the river segment below the lake, 24% continued to migrate and entered the river after approximately 5.7 days, as compared to 45% of the wild fish entering the river after approximately 2.3 days. Most of the stocked fish remained in the lower reaches of the river, upstream from the lake.
Non-predator and non-accidental mortality rates of bats inside the city of Toruń's fortification system (northern Poland) were studied over winter periods from 1995 to 2000. The bats were counted and dead bats collected at 1-month intervals from October to April. In total, thirty four dead bats were found. The percentage of dead individuals of the surveyed bats was low:Myotis daubentonii (0.6%),M. nattereri (0.4%),Plecotus auritus (0.4%),M. myotis (0.1%), and zero forBarbastella barbastellus. There was no clear difference in the species ratio of the observed and dead bats. The percentage of the dead to surveyed bats was lower in November (0.07%) and December (0.07%), and higher in September (3.3%) and April (1.3%). Temperature explained 84% of variation of the differences in mortality rates. Observations suggest that non-predator and non-accidental mortality inside the fortifications was extremely low and non-linearly correlated with the ambient temperature measured outside the fortifications.
The concentration of total iron and iron (II ) extracted by hot twice distilled water was analyzed in following medicinal plants collected from natural areas: St Johns wort (Hypericum perforatum L.), yarrow (Achillea millefolium L.), nettle (Urtica dioica L.) and birch (Betula pendula Roth.). Total iron was determined by FAAS method after microwave mineralization of samples, whereas Fe (II ) was extracted by twice distilled water in temperature of 85ºC and determined spectrophotometrically with use of o-phenantroline. The obtained results indicate that total iron content is from several dozen to more than 200 μg/g of dry plant weight and is correlated with plant species. In case of iron (II ) it was determined in amounts ten times less than total concentration of the element. It was noticed that level of that form of iron is positively related to total amount of iron in analyzed medicinal plants. Extremely high concentration of both forms of iron was characteristic for one sample of nettle collected in the Vistula Sand Bar. Based on the conducted research it is possible to state that iron on +2 oxidation state extracted by water can become a source of bioavailable form of this element for human.
W pracy przedstawiono wyniki badań dotyczące ciągów dni z opadem w chłodnym i ciepłym półroczu w czterech mezoregionach Polski Południowej. Wykorzystano sumy dobowe opadów atmosferycznych ze stacji meteorologicznych położonych w województwach: opolskim (Stare Olesno i Głubczyce) i małopolskim (Łapanów i Tuchów). Na podstawie uzyskanych wyników stwierdzono, że w latach 1971-2010 średnia liczba ciągów dni z opadem w półroczu chłodnym kształtowała się od 9,5 w Łapanowie do 11,3 w Starym Oleśnie, a w półroczu ciepłym od 10,1 w Łapanowie do 11,3 w Głubczycach. W obu sezonach najczęściej występowały ciągi trwające 4- 9 dni, nieco rzadziej obserwowano ciągi trwające 3 dni oraz 10-16 dni. Ciągi dni z opadem trwające dłużej niż 17 dni występowały rzadziej i zauważono, że najliczniej występowały one w Starym Oleśnie. W Głubczycach i Tuchowie w półroczu chłodnym stwierdzono istotne tendencje wzrostu liczby ciągów, natomiast w Głubczycach w półroczu ciepłym zanotowano zmniejszenie się ich liczby. W przypadku poszczególnych klas ciągów zauważono różne tendencje zmian liczby ciągów. Największe sumy opadów były związane z ciągami trwającymi 4-9 dni. W obu półroczach w Starym Oleśnie i Tuchowie, a w półroczu ciepłym Łapanowie, zwiększeniu liczby ciągów odpowiadał wzrost sumy opadów. Udział sum opadów występujących w ciągach w sumie opadów półroczy był zróżnicowany; w Głubczycach, Łapanowie i Tuchowie w półroczu chłodnym udział ten wykazał tendencję rosnącą.
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